Combined lift fork and bucket device for attachment to a vehicle

ABSTRACT

A device at a bucket (25,30), for example a so-called gravel bucket or transport bucket, which bucket is intended to be attached to a tractor or corresponding vehicle and be carried by preferably two lifting arms extending in parallel with each other, and where preferably hydraulic means are provided for controlling said lifting arms and said bucket so that the bucket can be lifted and lowered in a substantially vertical plane and be tipped. The device is especially characterized in that a lifting fork (21) or corresponding member is provided and intended to be carried by said lifting arms or corresponding members, which lifting fork (21) is mounted pivotal by preferably hydraulic means so that the arms (20) or corresponding members of the fork (21) can be pivoted in planes substantially perpendicular to the width direction of the bucket (25,30), and located substantially beneath said bucket (25,30). A further characterizing feature is that the bucket or portions (30) of the bucket (25,30) are capable, preferably by hydraulic means (40) to be folded to and from the fork (21 ) between a first and a second position, whereby the bucket (25,30), preferably resting on the fork (21), or the fork (21) can be utilized.

This invention relates to a device at a bucket, for example a so-calledgravel bucket or corresponding one, intended to be attached to a tractoror corresponding vehicle, comprising preferably two lifting arms capableto carry said bucket, where preferably hydraulic means are provided forcontrolling said lifting arms and said bucket, so that the bucket can belifted up and lowered in a substantially vertical plane and be tipped.

Buckets of this kind carried on tractors and corresponding vehicles areused for excavating and transporting, for example gravel etc. Certainapplications, however, for which the carrying vehicle, the tractor, perse would be suitable, cannot be carried out with a bucket. This applies,for example, to the lifting and transport of pallets and to the liftingand transport of cement pipes or the like. In such cases, fork trucksare used instead. It is, of course, possible to remove the bucket andexchange it for a lifting fork or the like, which requires normallytedious and stressing manual work.

The present invention relates to a combined excavating bucket andlifting fork, whereby a substantially higher flexibility in respect ofthe application range of the device is obtained. The device can beadjusted automatically for changing the field of application, i.e. forapplying the bucket or the fork.

The present invention, thus, relates to a device at a bucket, forexample a so-called gravel bucket or transport bucket, which bucket isintended to be attached to a tractor or corresponding vehicle and iscarried by preferably two lifting arms extending in parallel with eachother, and where preferably hydraulic means are provided for controllingsaid lifting arms and said bucket, so that the bucket can be lifted upand lowered in a substantially vertical plane and be tipped.

The device according to the invention is especially characterized inthat a lifting fork or corresponding member is provided and intended tobe carried by said lifting arms or corresponding members, which liftingfork is pivotal by preferably hydraulic means, so that the arms orcorresponding members of the fork can be pivoted in planes substantiallyperpendicular to the width direction of the bucket, which lifting forkis located substantially beneath said bucket, and that the bucket orparts thereof are capable, preferably by hydraulic means, to be foldedto and from the fork between a first and a second position, whereby thebucket, preferably resting on the fork, or the fork can be utilized.

The invention is described in greater detail below with reference to anembodiment and to the accompanying drawings, in which:

FIG. 1 schematically shows an embodiment of a device according to theinvention seen from the side, i.e. perpendicularly to the verticalplane, in which the bucket can be lifted and lowered, and in a sectionA--A according to FIG. 2,

FIG. 2 schematically shows the device according to FIG. 1 seen fromabove in FIG. 1,

FIG. 3 shows a detail of another embodiment where separate control meansfor the bucket are provided,

FIG. 4 schematically shows a preferred embodiment of a combined bucketand lifting fork according to the invention, seen in the width directionof the bucket,

FIG. 5 shows an enlarged forward portion of the bucket according to FIG.4, seen as in FIG. 4,

FIG. 6 shows an enlarged view of the fork arms and a back portion of thebucket according to FIG. 4, seen as in FIG. 4,

FIG. 7 shows half the arrangement of back portion and arms according toFIG. 4, seen from above in FIG. 6, and

FIG. 8 schematically shows a snow bucket intended to be attached to anarrangement of back portion and arms according to the invention.

In FIG. 1 a bucket, for example a so-called gravel bucket or transportbucket, is designated by 1, which bucket in known manner comprises abottom 2, end walls 3, a rear wall 4 and an opening 5. The bucket 1 isintended to be attached to a vehicle (not shown), for example a tractor,and to be carried by preferably two lifting arms 6 extending in parallelwith each other and capable by preferably hydraulic means, for examplehydraulic cylinders 7, to be controlled so that the bucket by pivotalmovement of the lifting arms 6 can be lifted and lowered in asubstantially vertical plane. The bucket 1 is hingedly attachedpreferably to the free ends 8 of said lifting arms 6.

According to the invention, also a lifting fork 9, for example aso-called pallet fork, or corresponding member is provided at andprojecting from the ends 8 of said lifting arms 6 carrying the bucket 1,which lifting fork is located substantially beneath the bucket 1.According to the embodiment shown in FIGS. 1 and 2, the lifting fork 9comprises a cross-piece 10, which extends between the lifting arms 6,and from which the arms 11 of the fork 9 project. The lifting fork isattached hingedly to the lifting arms 6 by means of a through axle 12 orcorresponding member extending between the lifting arms 6. Forcontrolling the fork 9, in connection to each lifting arm 6 a hydrauliccylinder 13 is provided which via two link arms 14, 15, of which one 14is hingedly attached to the lifting arm 6, act against a stay-shapedmember 16 of preferably the cross-piece 10 for rotating the fork 9 aboutthe axle 12.

The bucket 1 is hingedly attached to the ends 8 and capable in a firstposition to rest on the fork 9 with preferably portions of the bottom 2of the bucket 1, and in a second position to be located folded upward inthe direction away from the fork 9. The bucket 1 can here rest with itsrear wall 4 on said lifting arms 6 or on supporting members 17 comprisedin the lifting arms. In FIG. 1 said first position is shown by fullydrawn lines and said second position by dashed lines. According to apreferred embodiment, the bottom 2 of the bucket 1 comprises atunnel-shaped recess 18 for each one of the arms 11 of the fork. Also ata preferred embodiment, the bucket 1 is designed so that its bottom 2constitutes a substantially vertical rear supporting wall when thebucket is in said second position and the fork assumes loading andtransport position as shown in FIG. 1.

In FIG. 3 a hydraulic cylinder 19 is provided at a lifting arm 6 forfolding the bucket 1 between said first and said second position.Preferably two cylinders 19 are provided.

At the preferred embodiment shown in FIGS. 4-8, the numeral 20designates the arms of the liftinhg fork 21 comprised in the device.Each arm 20 is stronger than normal fork arms, for example of the typeused as a frozen soil scarifier, and provided with a tooth at theforward end, which arms 20 are intended to be used, for example, forloosening the material to be handled by the device. Each arm 20comprises at its rear portion an attachment portion 23 with attachmentholes 24, for example an upper and a lower one, for co-operation withlifting arms and control means, for example hydraulic cylinders, of atractor or similar vehicle. The fork 21 is capable to be controlled sothat the arms 20 can be pivoted in substantially vertical planes.

According to the invention, the bucket comprised in the device includestwo portions, a rear or back portion 25 located at the fork, the arms20, in connection to the attachment portions 23. The back portion 25comprises a rear portion 26, which extends in the width direction of thebucket and constitutes the back proper of the bucket, and two end wallportions 27 located at the rear portion 26 and extending forward, sothat a bucket-shaped back portion 25 is formed.

The back portion 25, at its lower forward portion, comprises preferablya plurality of attachments 28 arranged in the width direction of thebucket. In the figures only the attachments 28 located in connection tothe end wall portions 27 are shown. The attachments 28 are intended viaat least one through axle 29 or the like to co-operate with similarattachments of the forward portion of the bucket, as described below.

According to the invention, the bucket as mentioned also comprises aforward portion 30, which comprises the bottom 31 of the bucket 25, 30and end wall pieces 32 connected to said bottom. The forward portion 30comprises at its rear, lower portion 33 attachments 34 intended toco-operate with the attachments 28, so that the forward portion ishingedly connected to the unit formed of the fork and back portion. Theend wall pieces 32 preferably are sector-shaped, and the bottom 31 ofthe bucket includes elevated tunnel-shaped portions 35 for the arms 20whereby the forward portion can rest on the arms.

Inside of each end wall piece 32 and in connection to an attachment 34located adjacent the end wall piece, at least one rearward directedupward projecting link arm 36 is provided, which at its upper free end37 comprises an attachment 38 for a hydraulic cylinder or the like tofold the forward portion 30 between said positions. It can be imaginedthat only said bottom 31 can be folded, in which case the end wallpieces 32 are comprised in the back portion 25.

On each side of the bucket, FIG. 7, a space 39 is formed between the endwall piece 27 and a plane located outside the end wall portion 27, inwhich plane the corresponding end wall piece 32 can be folded. In saidspace 39 at least one hydraulic cylinder, FIG. 4, for folding theforward portion 30 is provided, which cylinder acts between theattachment 38 and an attachment 41 of the upper portion 42 of the backportion.

Each space 39 is formed by means of a U-shaped beam 43 or correspondingmember, which extends along the forward edge of the end wall portion 27,and which constitutes a protection for the cylinder 40 and comprisesguide members, for example an outwardly and upwardly located guide plate44, which is intended to co-operate with the edge portion 45 of an endwall piece 32, which guide members are capable to prevent deflection ofthe end wall piece 32 in the width direction of the bucket.

At the embodiment shown in FIGS. 4-8, the back portion 25 is rigidlyattached to the arms 20, and the rear portions 46 of the arms extendthrough recesses in the back portion, so that the back portionco-operates a.o. with the sides 47 of these arm portions. Complementaryattachment pieces 48 with attachments 49 are provided at the rearportion 26 of the back portion 25 in connection to the arms 20, asappears, for example, from FIG. 7. It is, however, possible to imagineembodiments, at which the back portion 25 is exchangeable at the arms20, whereby the width of the bucket can be varied by using back portionswith different width at the arms 20. The arms 20 and attachments, forco-operation with said lifting arms or corresponding members, preferablyare located in a suitable way in a self-supporting stable structure (notshown), for example by means of cross-stays or the like extendingbetween the arms in connection to the attachments. The back portion ismade exchangeable in a suitable way, for example by means of attachmentsprovided at the back portion to co-operate with the rear portion of thearms 11 and/or, when applicable, said self-supporting structure. Even atan exchangeable back portion 25, of course, complementary attachments 49can be provided at the back portion.

The forward portion 30 preferably is arranged removable, in which casethe foldable forward portion can be replaced, for example, by anunfoldable snow bucket 50, FIG. 5, which has a greater length than afoldable forward portion 30 and comprises tunnel-shaped spaces 51 forco-operation with the arms 20 and by means of attachments 52 at its rearportion, for example such as shown in FIG. 8, can be attached to theback portion 25.

According to a further embodiment of the device according to FIGS. 4-8,one or both arms 20 are movable in a suitable way in the width directionof the bucket, whereby the distance between the arms 20 can be adapted,for example, to the size of a stone or the like, which is to be loosenedor lifted by means of the arms 20. Hydraulic cylinders preferably areprovided for said movement, and in applicable cases the portions 53 ofthe back portion, which co-operate with the arm portions 46, areextended in the width direction of the bucket in an apparent manner, sothat space is provided for said movement. It is, of course, possible toarrange one or several arms 11 movable even at the embodiments accordingto FIGS. 1-3.

The mode of operation of the device according to the inventionsubstantially should have become apparent from the aforesaid. At theembodiment shown in FIGS. 1-3 the fork 9 is pivotal by means of thehydraulic cylinders 13. The fork can be pivoted downward to such anextent that the bucket can be tipped, and the fork can be pivoted upwardto such an extent that the bucket 1 by means of the fork 9 can be causedto assume said second position. When separate control means 19 areprovided for the bucket 1, the fork is not required to be pivoted upwardto such an extent. When the bucket 1 is in said second position, thefork can be utilized for pallet lifting, lifting of cement pipes etc.When the bucket is in said first position, the bucket can be utilized innormal manner. It is also possible to grip objects between the fork 9and the bucket 1 at least when separate control means 19 are provided.It is presupposed that the bucket and fork are designed and positionedso that a driver has an appropriate view from the driver's seat when thebucket assumes said second position and the fork 9 is in loadingposition.

As should have become apparent from the aforesaid, the device offers asimple and inexpensive solution of the problems referred to above in theintroductory portion. The device saves very much time and work and ishighly flexible in respect of its application range. At the preferredembodiment shown in FIGS. 4-8 is achieved that the operator has a verygood view even when the forward portion is folded upward, i.e. atexposed fork, due to the folding-up of only said bottom and end wallswhere rotation occurs about a centre located in connection to saidbottom. The structural design also is suitable for exchangeability ofbucket portions whereby, for example, the bucket width can be varied.The exchangeability is facilitated by the arrangement of the controlcylinders 40 at the bucket.

The invention has been described above with reference to someembodiments. It is, of course, possible to imagine more embodiments andminor alterations and completions without thereby abandoning theinvention idea.

At the embodiment shown in FIGS. 1-3, the members, link arms etc. forpivoting the fork can be designed in some other suitable way, moreprecisely for example substantially in the same way, which is utilizedfor the control of known buckets. Locking means 54, for example, can beprovided for locking the bucket in said second position where thelocking means 54 by way of example are indicated comprised in thesupporting members 17. The locking means may be mechanic, hydraulic etc.Due to the locking means, the bucket is retained in said second positionnot only because, as at the embodiment according to FIGS. 1 and 2, avertical movement upward of the point of gravity of the bucket isrequired for moving the bucket from the second to the first position.Furthermore, especially at the embodiment according to FIGS. 1 and 2,said tunnel-shaped recesses 18 can be imagined to comprisefriction-reducing members, such as rollers (not shown) or the likebecause a relative movement occurs between the "roof" 55 of the recessesand the upper surface of the fork arms when the bucket is operated bythe fork. The bucket, preferably in connection to the recesses 18, canbe completed with members (not shown), such as simple catches beneaththe fork arms, by means of which catches the bucket and fork can becoupled together so that the bucket can be moved from said secondposition by means of the fork.

At a device according to the invention apparently more arms 11, 20 canbe comprised in the fork. The arms 11, 20 can be of the reinforced typeas shown in FIGS. 4-8, or they may be for example pallet fork arms ofknown kind.

Attachment portions and attachments for co-operation with said liftingarms 6 or corresponding members, of course, can be arranged in severalways. It is preferable to arrange the arms 11, 20 substantially directlyin front of the lifting arms, wherby torsional moments about thelongitudinal direction of the arms 6 are avoided.

The invention, thus, must not be regarded restricted to the embodimentsset forth above, but can be varied within the scope of the attachedclaims.

I claim:
 1. A device comprising a combined assembly of a lifting forkand bucket, which is intended to be attached to a vehicle, said assemblybeing carried by means of lifting arms extending parallel to each other,and wherein means including hydraulic means are provided for controllingsaid lifting arms and said bucket so that at least the forward portionof the bucket can be lifted and lowered in a substantially verticalplane and be tipped, wherein a lifting fork is carried by said liftingarms, said lifting fork being pivotable by a further hydraulic means sothat the arms of said fork can be pivoted in planes substantiallyperpendicular to the width direction of said bucket, said fork beinglocated substantially beneath said bucket and wherein at least saidportion of the bucket is enabled by said hydraulic means to be folded toand from the fork between a first and a second position whereby thebucket, in said first position rests on the fork, and in the said secondposition is folded up away from said fork and back substantiallycompletely away from the vertical zone above the fork arms so that saidfork can be utilized in the conventional manner.
 2. A device as definedin claim 1 wherein said first named hydraulic means includes a specifichydraulic means connected to and providing said controlling of saidbucket, the bucket comprises a back portion, located at said forkconnected to attachments for co-operation with said lifting arms, and aforward portion comprising the bottom of the bucket and end wall piecesconnected to said bottom, and that the forward portion of the bucket ishingedly connected to the unit formed of the fork and back portion andfoldable by said specific hydraulic means between a first position wheresaid bottom is adjacent the arms of the fork and a second position wheresaid bottom is adjacent the back portion.
 3. A device as defined inclaim 2, wherein said back portion comprises a rear portion extending inthe width direction of the bucket substantially perpendicularly to thelongitudinal direction of the fork arms, and two end wall portionslocated at the rear portion and extending forward so that a bucket-likeback portion is formed.
 4. A device as defined in claim 2, wherein theback portion at its lower portion comprises a plurality of attachmentsarranged in the width direction of the bucket, which attachments includea through axle to co-operate with similar attachments on the forwardportion of the bucket.
 5. A device as defined in claim 3, wherein theouter surface of each end wall portion comprises guide members locatedoutwardly and upwardly and adapted to co-operate with the edge portionof an end wall piece, said guide members preventing deflection of theend wall piece in the width direction of the bucket and guiding the endwall piece during folding of the forward portion.
 6. A device as definedin claim 2, wherein at each side of the bucket, between an end wallportion of the back portion and a plane located outside the end wallportion, in which plane the corresponding end wall piece is foldable, aspace is formed, in which at least one hydraulic cylinder of saidspecific hydraulic means is provided for folding said forward portion,wherein each cylinder acts between an attachment on the lower portion ofthe forward portion and an attachment of the upper portion of the backportion.
 7. A device as defined in claim 2, wherein, said back portionis removable.
 8. A device as defined in claim 1 wherein the bucket isadapted in said second position to rest with its rear wall on supportingmembers comprised in the lifting arms.
 9. A device as defined in claim 1wherein locking members are provided for locking the bucket in saidsecond position.
 10. A device as defined in claim 1 wherein means areprovided, by which the bucket and fork can be coupled together, so thatthe bucket can be moved from said second position by the fork.
 11. Adevice as defined in claim 1 wherein the fork arms are of such size asto be able to loosen the material to be handled by the bucket, and eacharm at its free end comprises an excavation tooth.
 12. A device asdefined in claim 1 wherein the arms of the fork are locatedsubstantially directly in front of said lifting arms, whereby torsionalmoments about the longitudinal direction of the lifting armssubstantially are avoided.
 13. A device as defined in claim 1 wherein atleast a forward portion of the bucket is removable and replaceable by asnow bucket, which comprises tunnel-shaped spaces, into which the armsof the fork are intended to be inserted, and attachments, by means ofwhich the snow bucket is intended to be attached the end wall portionsof the back portions comprised in the bucket.